This invention generally relates to a device for repairing a junction between a lateral and main line. More particularly, this invention relates to a liner for improving junction repair sewer liner performance.
A known method of repairing an existing sewer pipe without excavation includes lining an existing sewer pipe with a resin impregnated felt liner. The resin impregnated felt liner is installed within the sewer pipe and held against the walls of the existing pipe until cured. During the curing process, it is desired that the resin adhere to the inner surface of the sewer pipe to provide the desired seal.
This cured liner substantially replaces the existing sewer by providing a new pipe within the existing old pipe. Repair of a junction between a main sewer pipe and a lateral sewer pipe includes a mainline liner portion and a lateral liner portion. In such installations it is desired to provide a seal. The seal of conventional liners depends on adhesion between the resin impregnated felt liner and the inner surface of the sewer pipe.
Disadvantageously, adhesion between the liner and the existing sewer pipe is not as complete as desired. Further, the curing process generates some shrinkage of the liner that also detracts from the desired seal.
Accordingly, it is desirable to develop a cured in place pipe liner repair that provides a desired seal between an existing sewer pipe and a liner that does not rely on adhesion between the existing sewer pipe and the cured in place felt liner.